git/compat/win32
Neeraj Singh abf38abec2 core.fsyncmethod: add writeout-only mode
This commit introduces the `core.fsyncMethod` configuration
knob, which can currently be set to `fsync` or `writeout-only`.

The new writeout-only mode attempts to tell the operating system to
flush its in-memory page cache to the storage hardware without issuing a
CACHE_FLUSH command to the storage controller.

Writeout-only fsync is significantly faster than a vanilla fsync on
common hardware, since data is written to a disk-side cache rather than
all the way to a durable medium. Later changes in this patch series will
take advantage of this primitive to implement batching of hardware
flushes.

When git_fsync is called with FSYNC_WRITEOUT_ONLY, it may fail and the
caller is expected to do an ordinary fsync as needed.

On Apple platforms, the fsync system call does not issue a CACHE_FLUSH
directive to the storage controller. This change updates fsync to do
fcntl(F_FULLFSYNC) to make fsync actually durable. We maintain parity
with existing behavior on Apple platforms by setting the default value
of the new core.fsyncMethod option.

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-10 15:10:22 -08:00
..
alloca.h mingw: activate alloca 2014-04-09 10:08:35 -07:00
dirent.c Win32: Unicode file name support (dirent) 2014-07-15 11:19:09 -07:00
dirent.h Win32: Unicode file name support (dirent) 2014-07-15 11:19:09 -07:00
flush.c core.fsyncmethod: add writeout-only mode 2022-03-10 15:10:22 -08:00
git.manifest mingw: embed a manifest to trick UAC into Doing The Right Thing 2019-06-27 12:55:45 -07:00
lazyload.h lazyload: use correct calling conventions 2022-01-09 10:34:53 -08:00
path-utils.c Sync with 2.20.2 2019-12-06 16:31:12 +01:00
path-utils.h run-command: trigger PATH lookup properly on Cygwin 2020-03-27 11:06:17 -07:00
pthread.c win32: replace pthread_cond_*() with much simpler code 2018-11-14 15:14:22 +09:00
pthread.h pthread.h: manually align parameter lists 2019-10-11 14:59:35 +09:00
syslog.c win32: plug memory leak on realloc() failure in syslog() 2017-08-10 13:57:52 -07:00
syslog.h mingw: implement syslog 2010-11-04 16:53:49 -07:00
trace2_win32_process_info.c lazyload: use correct calling conventions 2022-01-09 10:34:53 -08:00